color.loadProfile: say that a loaded profile lasts for the run (#1955)

The profile is registered in the process's colour registry only, so the
next `vectorcraft-cli run` (or the next launch of the app) doesn't know it
and edit.colorSettings falls back to the built-in profile. The command's
description now says so, and that the profile has to be loaded again in
each run that names it. Keeping profiles across runs would need a place in
the preferences to remember them, which is left for the maintainers.

crates/engine/src/cmd/colormgmt.rs

@@ -39,7 +39,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Load Color Profile…",
             [],
             None,
-            "{path: .icc/.icm file} register an ICC profile (native only) → {name, kind}",
+            "{path: .icc/.icm file} register an ICC profile until the app quits or the `run` ends (native only; it isn't remembered, so load it again in each run that names it) → {name, kind}",
             always,
             load_profile
         ),